Ventilating construction for dynamo-electric machines.



R. E. HELLMUND.

VENTILAHNG zuNsTRuCioN Fori :avremo summe MACHINES.

APPLICATION PILU! M105 lil-J.

1,238,292. lateutcd Aug. 28, 1917.'

UNITED STATES PATENT OFFICE.

RUDOLF E. HELLMUND, 0F PITTSBURGH, IPENNSYLVANIA, ASSIGNOR TO WESTING- iHOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION OF PENN-SYLVANIA.

VENTILATING' CONSTRUCTION FOR DYNAMO-ELECTRIC MACHINES.

Specification of Letters Paten .Patented Aug. 28, 1917.

Application filed August 6, 1915. Serial No. 43,99811,

Y?) all whom it may concern:

Be it known that I, RUDOLF E. H nnLuUSn, a subject ol' the Emperor ofGermany, and a resident of Pittsburgh, in the county of Alle gheuy andState of Pennsylvania., have invented :t new and useful improvement inVentilating Constructions 4 for Dynamo- Electric Machines, of which thefollowing is a specification.

My invention relates to dynamo-electric machines provided withforced-draft venti lating means. and it has special reference to motorsfor railway service in which ventilating currents of air are causedtopass through end openings in the motor armatures by means of fanssecured to the armature shafts.

The objects of m. invention are to improve the eicieney of Ventilatingdevices of the above indicated character and to prevent the entrance ofwater, or other foreign substances,through the ventilating openings.

In the accompanying drawing, Figure-Ltb is an axial sectional view of aportion of a railway motor equipped with Ventilating means constructedin accordance with my invention, and Fig. 2 is a transverse sectionalview taken partially along the line H-II and partially along the lineIII-III of Fig. 1.

In ventilated railway motors of the type in which the circulation of airis accomplished by means of centrifugal fans adapted to draw air throughthe armature and discharge it through openings in the motor housingadjacent to the fan, the most eiii- -cient ventilation can be obtainedif the airy leaving the tan is permitted to escape directly from themotor housing without being deflected. Such an arrangement, however,

has the disadvantage that water, snow and other foreign substances canreadily enter through the discharge openings and reach the armature corethrough the fan and its supply openings. According to my presentinvention, I so -construct the air passages associated with the fan thatany water which may enter the fan is trapped and drained out of themotor without entering the armature core.

Referring to the accompanying drawing,V

the machine here shown comprises a stationary frame 1 having eld-m,agnet colls 2 mounted on polar projections 3, a bearingi housing 4and an armature having a lami natcd core nwmbcr .3, a winding (i and ashaft T. 'lhc armature shaft is rotatably supported in bearings, one ofwhich is shown at associated with the hearing housing 4.

The laminated core member 5 of the armature is provided withlongitudinal passages E), and a centrifugal fan 10provided withradhilly-extending blades 11 confined between annular plates 12, issecured to the shaft, between the arn'iature core 5 and the bearing 8.

Adjacent to the outer periphery of the fan 10. the hearing housing 4 isprovided with a series of discharge openings13, shown in Fig. 1. .Itwill be noted that air discharged from the fan is enabled to assdirectlrthrongh the openings 13 wit out deflection. The inner end ofeach of the passages formed h v the fan blades 11 and the plates' thedrawing, currents of air are caused to pass through the Ventilatingpassages 9, by means of' the fan 10, in the directions indicated by thearrows in Fig. 1. Any'water or other foreign substance which may enterthe fan through the openin 13 is trapped in the depressions 14 an isdischarged through the lower o enings 13 by the centrifugal force of thean, assisted by gravity. The free escape of air from-the fan is,therefore, unobstructed, while the entrance of water into the motor iseiectually pre-- vented. Y

It isto be understood that-myinvention is notl restricted to the precisestructural details which I have shown and described, but that anymodifications may be effected within the spirit of my invention whichfall within the scope ofthe appended claims.

Iclaim as my invention:

1. In a dynamo-electric machine, the combination with a stationarymember, a rota.- table member provided with longitudinal Ventilatingpassages, a casing inclosing the said members and provided withVentilating enter the fan throu openings, and a fan embodying n set otair passages communicating with the ventilating passages in the sindrotatable member and anothci set of passages communicating directly withsaid Ventilating openings, of means located intermediate the said setsof passages for trapping foreign matter that may enter the fan throughseid openings.

2. In a dynamo-electric machine, the combination with a stationarymember, a rotatable member,V a casing inclosing the said members andprovided with openings for the passage of air, and a ventilating fan as-Sociabed with the-said rotatable member and having a direct andunobstructed communication with the external atmosphere through ,thesaid openings, of means for trapping foreign matter that may enter thefan through the said openings.

3. A dynamoeleetric machine comprising a stationary member, a, rotatablemember, n casing inelosing the said members and pro` vided with openingsfor the passage of air, and a Ventilating fan associated with the saidrotatable member and embodying a trap for stopping foreign. matter thatmay h the said openings.

'4. In a dynamo-e estrie machine, the combination with a stiitionurvmember. n. rotafor the passage of air, and a fan embodying air passagescommunicating With the venti' lating passages in the said rotatablemember and adapted to force air directly, and without deflection,through the openings in the seid casing, of means located at theentrance to the said air passages for trapping foreign matter that muyenter the fan.

5. A dynamo-electric machine comprising a stationar member, a rotatablemember }V=rovided with longitudinal Ventilating passages, a easinginelosing the said members and provided with openings for the passage ofair, and a fan embodying air passages communicating with the Ventilatingpassages in the said rotatable member and other radially-disposeddirectly toward the o enings in the said casing, the inner end o each ofthe said'radially-disposed passages being provided with a water-trappingdepression.

In testimony whereof, I have hereunto subscribed my name this 29th dayof July 1915.

RUDOLF E. HELLMUND.

passages opening Y

